Carrying mechanism for calculating



J CARLSEN 2,503,613 CARRYING MECHANISM FOR CALCULATING MACHINES Filed Oct. 14, 1946 M/ENTDI I i q (mica;

,ITTL'XWIEKF April 11, 1950 Patented Apr. 11, 1950 -i PATENT OFFICE CARRYING MECHANISM E'g oALoULATmG MACHIN Johnvfiarlsen Hellerup, by Copenhagen, Denmark" Applicati'onqctober "14, 1946; Serial "'N o; 703247 In Denmark'October '18; 1945 1 Claim; 1

The present invention relates' tdthe carrying mechanism of calculating machines. of the: 1 kind in -which the number wheels are turned by tiepressing" the amount keys; and in which the: calculating unit for' the numeralsof' each de- 6 nomination-,with theexcep'tion of the highest; comprises a carrying member which; in thecase of a" calculating operation a, in the unit in ques ti'onrequiring a carrying operation, is 'released soas to be permittedito performa carrying "move- 10 ment.

If incalculating machines of this kind, keys belonging to twovneighbouring" calculating units are :siinultaneously' depressed as V is particularly I the casewhen such machines are employedfor multiplication, it may-occurthat, while an addition is taking place in the calculating unit of the higher-'order u-nder'the influence of the depression of a key 'belongingtosuch calculating. unit; a carry"'ti'ansfer"to this calculati'ng'unit is': at the-same time initiated J from the calculating unit of the lower: order as i a consequence- 0f av key belonging-to the latter'being' depressed. If the": two impulses thus created: for. turning the number wheel ofthe calculating ur-iit o f the high-' e1-= order happen' to'overlap' in" time, an error in calculation 1 may occun because in the overlap; ping" period no addition will take place of the movements of the number wheel which eachsof; theitwo timpu-lses; if i'acting' alone; would betcapable 0f creating-i To avoidxthei possibility oi such 1 errors, .it has: been'.=v proposed to provide each I calculating unit; to. which 1 a carry, transfer may tak'e place from a calculating unit of lower order; with a trans- 5 fer"locl'c-= adapted to prevent the possibility" of I a carry transfer to the calculating unit a in question'; asxlo'n'g as B a calculating operation" is tak'- ing' place: within' such calculatingunit on account of the de 'aression of a keyin'the row f 40 keys belonging to same; The transfer lock is constructed in such aimannenthat 'onthe depression :of-ranykeyib elonging' to thel calculating' unit 1 in:.qu'estion -for1" the purpose: of f the following; specification? to bereferred to i as 1 the? receiving; calculating unit as distinguished from the int tiatingzcalculating unit; i;- cg: the ca'lculating unit: on the; nextiflower' denomination which initiates the. carrying op'erationit is: caused to assume 1 ailock-ing or barring'position preventing thescar rying member of the initiatingi calculating unit 4- from performing its". carrying movement. Accordingly. the carrying. operation cannot take place: until the transfers loclc has been moved from: the 'said: barring: position to a: re1easing;.-

position, which. takesiplace" only when the depressed. key'of the receivingcalculating unit has been releasedand has returnedto its normal position.

Thespresentinvention isbased on the recognition that'. the employment of a" transfer lock on'these llines'doesunot'afford full security against the'o'verlapping.of'anfoperation of simple addibecomes effective and if now the'carry transfer from the initiating.v calculating. unit should take place before the said'amount of the depression movement' ha's. beencompleted, the above mentioncd'error may occur. Itmight seem possible toobtainzsecurity. against this error: by. arrangingifor theamount of depression necessary, in the receiving calculating. unit in order: to bring the transfer 'lock'intoaction-to be smaller than the:

smallest amount of depression in the initiating calculating; unit capable of initiating the carryingioperatiombut as amatter of fact no real securityi-is ob'tained in this manner, because two simultaneously depressed keys of the receivingv andvth'e initiating. calculating unit respectively are:not-synchronized in their movements, but

ar'e 'depressed by, means of individual fingers.

so that, under unfavourable conditions, it may occur: that theikey of the initiating calculating unit-is far advanced in its depression movementrelativ ely:-'tov the key. of the Y receiving calculating.

units.

Thiswkind of error in calculation will of course be very.=rare, .indeed such that it will hardly be possible-to"reproducesuch an error if it is ascertained. But-that'is particularly why such anerro is'to be considered extra grave, because the operator: will then "be inclined to satisfy himself inithe belief that he :has pressed the wrong key the first time, or perhaps he will send the machine-to a: service :agency. for inspection without the latter beingicapableof bringingjto light the reason whythe'error came about.-

The present invention has for its purpose toeliminate .this drawback, and this is obtained by arranging-for: the initiating calculating unit to control the transfer lock. According to my invention'thecarrying operation does not take placeuntil the depressedkey of the initiating calculating; unit has :practically. returned to its original position.- Thus there is no possibility from the following description of an embodiment.

of the invention as applied to a five key calculating machine, i. e. a machine of the type having keys only for the numerals 1-5 in each column,

the addition of the higher numerals being effected by striking twice, e. g. 2x3 instead of 6, 3+4 instead of 7 etc. the accompanying drawings in which Fig. 1 shows a calculating unit representing the numerals of one order in a calculating machine provided with carrying mechanism according to the invention, as viewed in side elevation, and

Fig. 2 shows the same in plan view.

There are five key arms H-l5, each carrying a key representing the numerals 1-5 respectively. Of these keys only the key representing the amount 5 is shown in the drawing. The key arms [1-15 are arranged in juxtaposite relationship so as to form a fan-like structure, and all the key arms are pivotable on a common pivot IS. The key arm is provided with a stud l1 engaged in elongated slots l8, I9, '20 and 2| of the key arms I I, l2, l3 and 14, so that on the depression on any of the keys fixed to the key arms H-i5, the key arm l5 will be swung downwards on the pivot IS. The angle through which each key arm ll| 5 is depressed until striking the base of the machine as represented at 50 will be proportional to the number represented by the key in question, and since each of the key arms I l-l4 on being depressed carries with it the key arm l5 through its entire stroke, the angle through which the key arm I5 is moved will always be pro- Reference will now be had to edge 43 of a hole 44 in the partition 4| between the considered calculating unit and the calculating unit of the next higher order. The carrying member '21 is provided with a toothed sector 29 adapted to cooperate with a number of projecting teeth on the end surface of the number wheel 24. The lowermost tooth 29a of the toothed sector 29 is bent out of the overall plane of the toothed sector in the direction towards the number wheel 24, while the other teeth 29b, 29c and 29d of the toothed sector are bent out of its plane 'in the opposite direction. Similarly the leading in which the teeth 29b, 29c and 29d mesh with the teeth 36b, 30c and 30d.

The characteristic feature of the invention is represented by a transfer lock in the form of a U- shaped barring member 32, the body 33 of which rests on the top edge of the key arm l5, while with its shanks 3'4 and it is rotatably mounted portional to the number represented by the depressed key. The detailed construction of the key system is the subject matter of my co-pending application No. 628,698, filed on November 15, 1945, now U. S. Letters Patent No. 2, 7 2,519, and

has no direct bearing on the present invention,

so that a further description is considered uncation.

The key arm 15 carries a toothed sector 22, which by means of a gear wheel and a ratchet drive operates a number wheel 24 in such a manner that on the depression of any key the number wheel will be advanced through an angle corresponding to the number represented by the depressed key, such turning of the number wheel taking place simultaneously with the depression of the key. A pawl '25 co-operating with teeth 26 of the number wheel serves to brake the number wheel and to arrest it in its prescribed positions.

The number wheel 24 cooperates with a carrying member 21 serving to carry forward one to the calculating unit of the next higher order when the number wheel 24 passes through the zero position. The carrying member 2! is pivoted at 28 and is loaded by a spring 3| tending to turn it in an anticlockwise direction. Thus, when not subjected to other influences the carrying member will not be in the position shown in Figs. 1 and 2, but in a position swung so far in an anticlockwise direction that an abutment carried by the carrying member is in contact with the calculating unit shown, i. e. the initiating cal-- culating unit, but only after the calculating opnext lower order of which no other details are on a pin 38.

A torsional spring 31 tends to keep the body 33 of the barring member in constant contact with the key arm Hi. The shank 35 of the barring member 32 is provided with a detent 538 co-operating with the back of the toothed Each time the key arm I5 is de-- sector 29. pressed, the said detent 38 is moved towards the back of the toothed sector 29 under the influence As long as the carrying memf ber 21 has not yet been turned to its position of release, i. e. the position in which it is released of the spring 31.

by the teeth 30 of the number wheel 24, the said movement of the detent 38 towards the back of the toothed sector 29 will be without efiect, but

immediately before the carrying member 21 comes into the position of release, the detent 38 will be capable of snapping in behind a shoulder 39 provided at the back of the toothed sector so as to keep the carrying member 27 barred or locked .in the position of release, until the detent 38 on the barring member 32 is again moved toward the left, which takes place only when the key arm i5 has been practically restored to its normal position.

Thus, it will be realized that the barring member 32 has the efiect that no carry transfer to the calculating unit of the next higher order, i. e. the receiving calculating unit, can take place during the initiating calculating operation in the eration has been completed and the depressed key has practically returned to its original position. In other words, the barring member 32 forms a transfer lock which is controlled by the initiating calculating unit.

All the parts so far described belong to the calculating unit of one order, and in the embodiment shown are situated in the space between two partitions 40 and M. any number of calculating units may be provided at both sides of the one shown. 21 is a carrying member exactly similar to the carrying member 21, but belonging to the calculating unit of the from the calculating unit of the next lower order.

It will be understoodthat the carrying member 2'! is provided with a pawl (not shown) exactly As will be understood, 1

similar to the pawl 42' for the purpose of transfer from the calculating unit shown to the calculating unit of the next higher order.

The operation is as follows: When the carrying member 2'! is in its position of rest with its abutment 45 in contact with the edge 43 of the hole 44, the toothed sector 29 will be engaged by the teeth 30 of the number wheel 24 when the number wheel 24 has been turned to its "5 position. Upon further rotation of the number wheel by depression of the keys, the number wheel will therefore cause the carrying member 21 to be rotated in a clockwise direction against the action of the spring 3| which is thereby strained or wound up, the teeth 30 preventing the toothed sector 29 and thereby the carrying member 21 from returning to its neutral position under the influence of the spring 3|.

Figs. 1 and 2 show the number wheel in the zero position immediately after the carrying member has been fully released for return movement. It will be understood that in the zero position the tooth 30d has just left hold of the tooth 29d thus permitting the carrying member 21 to be rotated in an anticlockwise direction under the influence of its spring 3|. However, as will be apparent from the above description of the transfer lock, this rotation of the carrying member may take place only after the key, the depression of which caused the number wheel to be rotated to the zero position, has been restored to normal as shown, because as long as this is not the case the detent 38 will engage behind the shoulder 39 and detain the carrying member 21 in the position shown.

When the carrying member 21 is turned in an anticlockwise direction under the influence of its spring 3|, it will effect a carry transfer to the numerical group of the next higher denomination by means of the above named pawl, not shown, exactly similar to the pawl 42.

No claim is made herein to the 5-0 transfer drive which forms the subject matter of my co- 6 pending application Serial No. 703,248 filed 0ctober 14, 1946, now abandoned, or to the staggered tooth transfer drive forming the subject matter of my copending application Serial No. 703,249, filed October 14, 1946, now Patent No. 2,499,946.

Having now particularly described and ascertained the nature of my invention and in what manner the same is to be performed I declare that what I claim is:

In five-key calculating machines, a number wheel of lower order, a set of five keys of lower order cooperating with said number wheel for rotation thereof on depression of any one of said keys, a spring biased transfer member operatively associated with said number wheel of lower order to be moved thereby during part of a revolution of said number wheel and thereafter released to perform a return stroke, a transfer lock individual to said set of keys of lower order and movable on depression of any of said keys of lower order to a position to engage with said transfer member to prevent return movement thereof and on the substantially complete return movement of said keys of lower order said lock being movable to a position to permit the return stroke of said transfer member, a number wheel of higher order, and means associated with said transfer member for imparting transfer motion to said number wheel of higher order from said transfer member during the return stroke thereof.

JOHN CARLSEN.

REFERENCES CITED The following references are of record in the 

